I collated this set of links about hyperbolic geometry while working with SUMaC during the northern summer 2007. I expect they will get out of date very quickly but at the time I collected this list it seemed better than any other similar compilation on the internet. They were updated in November 2008.

Wikipedia on hyperbolic geometry

Pages with lots of links:

Interactive Java applets

- Lots of pages of good interactive java applets on hyperbolic geometry, using cabri.
- Java applet for hyperbolic triangle area

From the geometry center

:

- Colleen Robles (some pictures)
- Hyperbolic triangle area (applet)
- Geometry forum
- Models of the hyperbolic plane
- Pictures from video “Not knot”
- Pictures of the hyperbolic plane
- 237 tiling
- About Jeff Weeks software
- Shape of Space video
- Teichmuller navigator

From “Geometry and the Imagination”

- Projects
- Curvature of surfaces: This page and this one too

Hyperbolic tessellations/tilings

- Tessellations with Schlafli symbols
- Gallery by Bernie Friedin
- Escher-style tilings, including hyperbolic ones
- Penguins by Misha Kapovich

Hyperbolic tessellations by Sascha Rogmann:

From M.C. Escher

:

- Circle Limit III: 1959 woodcut, second state, in yellow, green, blue, brown and black, printed from 5 blocks
- Circle Limit IV: 1960 woodcut in black and ocre, printed from 2 blocks

Popular Articles

- Visions of Infinity: Tiling a hyperbolic floor inspires both mathematics and art. From sciencenews.org.
- Interview in Cabinet magazine on hyperbolic crochet

Jeff Weeks software

:

- KaleidoTile: Polyhedra and tilings
- Curved Spaces: Flight simulator

Other Software

- NonEuclid: Java software for ruler/compass constructions in hyperbolic geometry

YouTube

- Not Knot (1/2)
- Not Knot (2/2)
- Hyperbolic geometry song (requires stomach)
- Moebius transformations revealed

The Institute for Figuring has a very slick gallery of hyperbolic stuff, including crochet:

- Crochet article
- Reported in the Christian Science Monitor
- LA Times article on crochet
- NY Times article on crochet
- NPR (with mp3) on crochet
- Science article on crochet
- Bangor daily news article on crochet
- Blog entry on crochet:

Tractrices

- Tractrix and “tractional movement” in geometry (in French)
- Tractrix and pseudosphere
- Relationship between tractrix and other models

Random other links

- Neutral and non-euclidean geometries by David C. Royster
- Sewing a two-holed cloth torus
- Hyperbolic surfaces in nature, including hyperbolic paper
- Cool animated gif of a parabolic I saw randomly on a blog

Hyperbolic links